试述实践中测量不确定度的来源。

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问题问答题简答题

试述实践中测量不确定度的来源。

答案

参考答案：

在实践中，测量不确定度可能来源于以下10个方面：①对被测量的定义不完整或不完善；②实现被测量的定义的方法不理想；③取样的代表性不够，即被测量的样本不能代表所定义的被测量；④对测量过程受环境影响的认识不周全，或对环境条件的测量与控制不完善：⑤对仪器的读数存在人为的偏移：⑥测量仪器的分辨力或鉴别力不够；⑦赋予计量标准的值和标准物质的值不准：⑧引用于数据计算的常量和其他参数不准；⑨测量方法和测量程序的近似性和假定性；⑩在表面上看来完全相同的条件下，被测量重复观测值的变化。

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The research carried out by the University of Bad in Italy could help prove hospitals who are accused of wasting money on art and decoration as it suggests a pleasant environment helps patients ease discomfort and pain.

A team headed by Professor Marina de Tommaso at the Neurophysiopathology

Pain Unit asked a group of men and women to pick the 20 paintings they considered

most ugly and most beautiful from a selection of 300 works by artists such as

Leonardo da Vinci and Sandro Botticelli. They were then asked to look at either the beautiful paintings, or the ugly painting, or a blank panel while the team zapped(照射) a short laser pulse at their hand, creating a sensation as if they had been stuck by a pin. The subjects rated the pain as being a third less intense while they were

viewing the beautiful paintings, compared with when looking at the ugly paintings

or the blank panel. Electrodes measuring the brain's electrical activity also confirmed a reduced resoonse to the pain when the subject looked at beautiful paintings.

While distractions, such as music, are known to reduce pain in hospital patients,Prof de Tommaso says this is the first result to show that beauty plays a part.

The findings, reported in New Scientist, also go a long way to show that

beaufiful surroundings could aid the healing process.

"Hospitals have been designed to be functional, but we think that their artistic aspects should be taken into account too," said the neurologist."Beauty boyiously offers a distraction that ugly paintings do not. But at least there is no suggestion that ugly surroundings make the pain worse. I think these results show that more research is needed into the field how a beautiful environment can alleviate suffering."

Pictures they liked included Starry Night by Vincent Van Gogh and Botticellis Birth of Venus. Pictures they found ugly included works by pablo Picasso, the Italian 20th century artist Anonio Bueno and Columbian Fernando Botero." These people were not art experts so some of the pictures they found ugly would be considered masterpieces by the art world," said Prof de Tommaso.